Transcript Planets

Planets
Surfaces of planets have a….
1. Terrestrial or Rocky Surface (Inner Planets)
Mercury, Venus, Earth, and Mars
2. Gaseous Surface (Outer Planets)
Jupiter, Saturn, Uranus, and Neptune
Gaseous Planets are
considerably
LARGER!
Saturn has a
diameter 9.4 times
larger than Earth’s.
SATURN’S Diameter=
120,200 kilometers
Made of Helium and
Hydrogen.
( Has a small, rocky core)
Question 1: Which
celestial object has a
similar composition to
Saturn?
Planets may have
RINGS!!
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Made of rock and/or ice.
Gravity breaks up debris to form them.
Sometimes even their own Moons.
Size of particles: 1mm-10 m in diameter!
Such as: Jupiter, Saturn,
Uranus, and Neptune.
Movement of Planets is based on
revolution around the …
SUN
All current planets are on
the same plane.
Pluto is 17° off the plane.
Question 3: What
is this?
Movement of Planets is also
based on rotation around its…
AXIS
Moons
Moons are studied
in relation to the
planet they…
ORBIT
Not all planets have
moons, such as…
MERCURY AND VENUS
Question 4: Besides the
moon, what else orbits
the Earth?
Asteroids:
Astronomers thought at one time…
There were 13 planets.
The 9 we are aware of (includes Pluto) and
Ceres, Vesta, Juno, and Pallas.
They were found in between Mars and Jupiter.
One by one, they found many more objects like
the 4 “new planets”.
So, they changed
them from “planets” to
“dwarf planets” and
identified their location
as the asteroid belt.
Asteroids cont.
The ASTEROID BELT is located between
the inner planets and the outer planets.
Asteroid Size: Rocks greater than 100 m
in diameter.
What do asteroids
revolve?
COMETS
The main body or head is
composed of ice and rock particles
mixed with gas, methane and
ammonia…
Tail
Head
…and a TAIL that emerges as the
comet gets CLOSER to the sun
during its orbit.
Question 5:
Why does the
tail emerge?
The tail always points
_________ from the Sun.
Comets have a Question 6:
Why would this
unique long,
be true?
narrow
________________
orbit.
Located at the very edge of
the Solar System. Past
Neptune’s orbit.
METEOROIDS
Chunks of rock that move about the Solar
System.
Size of meteoroid: Less than 100 m in
diameter.
Smaller than asteroids.
Could be part of
old comets so
they are also…
smaller than comets.
Russia Meteorite
Can be called…
A meteor : A meteoroid that burns up
in the Earth’s atmosphere. (AKA Shooting Star)
OR
http://www.meteorcrater.com/
A meteorite: A meteoroid that strikes
a planet or moon.
Pluto debate:
http://www.youtube.com/watch?v=FqX2YdnwtRc
Pluto is located in the
“Kuiper Belt” (Outside
Neptune’s orbit).
It is similar to the
asteroid belt, but all
material is made of
ice/rocks (too far from
the Sun).
Astronomers found
many “objects” in the
same location,
recently.
Made them think back
to Ceres, Vesta, Pallas,
and Juno.
So, the International
Astronomical Union
(IAU) met in 2006 to
settle the matter.
Decided Pluto would be
considered a “Dwarf
Planet”.
The “dwarf planets” are
round like planets, but
do not clear out their
orbits of debris.
Take a moment to answer the
“Follow-Up Questions” on
your own.
Try not to use your notes…
Add the following terms to your
“SUPER CONCEPT MAP” list
on the bottom of p. 23:
oCeres
oAsteroids
oIAU
o8
oPluto
oComets
oKuiper Belt
oRings
oOrbit
oRock
oMeteors
oMoons
oMeteoroids
oSun
oAsteroid Belt